Why can't I get an erection?

Willful and capricious – erections are funny things. When you're a young man, they seem to pop up at the most inappropriate moments (and the only thing between you and embarrassment is a carefully placed notebook). As you get older, however, they go the other way, and fail to appear on demand no matter how much you try. The sad thing is, my patients often equate this with a loss of masculinity.

Advertisement - Continue Reading Below

Working out why your erection might be letting you down is more of an art than you'd think – and more important to your GP than you might feel is necessary!

First, how do erections work?

Men are very susceptible to visual stimulation, particularly as children and teenagers. Seeing anything appealing (say, a person or image) activates pathways in the brain that tell nerves in your lower spinal cord to trigger a release of nitric oxide, which relaxes blood vessel walls and floods your penis with blood, making it hard. Nitric oxide is the key chemical here, as you need a mix released from your nerves AND from your blood vessels to get an erection. If the blood vessels, nerves, or both are damaged, it's difficult to get a hard erection. That's why your doctor may well be interested if you're struggling with erections, as it could be a sign of early heart disease or diabetes.

Why am I losing my erections?

There are lots of reasons why men can't get erections, and for many there is more than one cause of erectile dysfunction. But the causes can be broken down into two main areas: psychosocial and medical.

Psychosocial factors

An erection depends on you being relaxed. The problem is, the sympathetic nervous system actively suppresses erections, something at least partly learned during childhood and the teen years (it's not good manners to have an erection in assembly, is it?). So we learn to inhibit our erections as standard.

Advertisement - Continue Reading Below

That means that as an adult, you need to activate the opposing parasympathetic system through sexually exciting visuals, thoughts and touches to get an erection going. But this nerve transmission is disrupted if you're stressed, anxious or distracted. The latter because you simply don't develop enough total stimulation of your genitals to get an erection, and the former because stress and anxiety all increase adrenaline – a key transmitter in the inhibiting sympathetic nervous system. They quite literally sabotage your erection.

Medical factors

The main medical causes of erectile dysfunction are based around poor blood flow (due to furring of the arteries thanks to raised cholesterol or high blood pressure), poor nerve supply caused by diabetes-related nerve damage, or low testosterone as a result of obesity, old age or failing gonads. We doctors get just as concerned with men who have variable erections as well as those that can't get an erection at all. Failing to get an erection occasionally is pretty normal as you get older. But if you have unreliable erections for a prolonged period of time – more than six months – this could suggest an early sign of physical problems such as cardiovascular disease or diabetes which could develop further so get yourself checked out.

A mix of the two

A lot of the time, the issue is a combination of both. For instance, cortisol – which is an important steroid hormone in the body – is released in greater amounts when we're stressed. It's supposed to briefly shut down non-essential functions like reproduction and fighting off illnesses whilst you deal with the danger at hand. However, the chronic and ongoing stress of modern life increases our background cortisol levels, activating the sympathetic system and stopping an erection.

Poor sleep is another such example, as the result of insomnia (or young children) can affect erections, again at least partially by increasing stress hormones in the body.

Other factors affecting your erections

Alcohol plays a negative role when it comes to your erections. Drink may reduce stress and inhibitions, but it also reduces transmission to your genitals. I advise men who have erectile dysfunction not to drink alcohol.

Advertisement - Continue Reading Below

Advertisement - Continue Reading Below

Drugs such as cannabis reduce both the desire and drive to have sex. Cocaine and ecstasy may impair erections or significantly delay/prevent ejaculation and orgasm. Not ideal.

Cycling. Seriously. Those hard saddles cause significant pressure on the perineum (the area between your scrotum and anus) which can compress nerves supplying the penis. Compressing these nerves firmly over a period of time puts them, temporarily, to sleep. Use a softer, padded saddle or take up swimming – an exercise which can also help with relaxation. If cycling is genuinely the cause, erections should improve after two to three months when the compression resolves.

Clogged arteries.Your penis is an extension of your blood supply, and the smooth muscle walls of the penis tissue – assisted by nitric oxide – relax to fill with blood. If these penile arteries supplying blood are furred up, you're going to struggle to get the 'filling' pressure you need. Blood vessels fur up for lots of reasons including:

High cholesterol

Raised blood pressure

Nicotine (cigarettes or vapes)

Diabetes

Obesity

Family history of heart disease

Penile arteries are 1-2mm wide so if they are furring up, your coronary arteries (at 3-4mm) which supply your heart will be too. The carotid arteries (at 5-7mm) that supply your brain are a bit wider so they won't fur up as early – but this is why doctors would want to know if ED an issue for you.

If you can reduce cholesterol, improve lifestyle, lose weight, stop smoking, and we doctors can help with medication where necessary, you are much more likely to gain back use of your penis AND reduce your risk of a heart attack or stroke.

Could testosterone be to blame?

Advertisement - Continue Reading Below

It's unlikely. Testosterone levels fall as you get older but they have to fall really low to cause erectile problems. Thus assessment for erectile dysfunction includes a testosterone blood test but only replacement if it is very low. Giving someone more testosterone than their body would have made, even at a young age, can cause blood clots due to blood thickening and even reversible infertility. So don't be tempted with homespun remedies.

Modern lives = sexual dysfunction

This may sound depressing, but it highlights to me how stressful our lives can be. If you are experiencing sexual dysfunction it may be a wake-up call to check out your general health. You can make a start on improving sexual function straight away by

Reducing stress

Enjoying more foreplay

Eating a healthier diet

Doing more (or some) cardiovascular exercise

The latter two have been shown by multiple studies to increase erections and testosterone levels without any need for medication.

NetDoctor, part of the Hearst UK wellbeing network
Netdoctor participates in various affiliate marketing programs, which means we may get paid commissions on editorially chosen products purchased through our links to retailer sites.